1. Field of the Invention
The invention relates in general to binder spines, and, more systems of binder spines.
2. Description of the Prior Art
Binder spines have been proposed for holding loose papers together. The prior proposed expedients are not without their shortcomings. Major shortcomings of typical prior binder spines include, for example, complexity, cost, and difficulty of use. Previous expedients did not generally include the provision of a system of binders that provide increased utility to the user yet permit the manufacturer to readily supply a system including a plurality of binder spines with different capacities.
Previously proposed expedients include, for example, Wu US Des. 360,221, Exline U.S. Pat. No. 0,847,389 (check book binder with spring loaded engagement of securing posts with deformed tubes), McKowen U.S. Pat. No. 3,260,264 (a binding for books composed of a molded one-piece binding unit with living hinges, binding posts, and a port in which a mushroom head of the binding post engages), Cott U.S. Pat. No. 3,574,472 (a molded one-piece binder for perforated loose leaf sheets wherein a headed post is inserted into an open sided groove to hold the binder in a closed configuration), Errichiello U.S. Pat. No. 4,307,972 (a molded one-piece loose leaf book with plastic posts wherein a headed post frictionally engages a tubular post), Jahn U.S. Pat. No. 4,340,316 (a binder in which a barb headed post engages an open sided slot), Chin U.S. Pat. No. 5,865,469 (a binding bar for a cover folder in which the edges of the binder bar engage barbs in the cover), and Jahn U.S. Pat. No. 6,076,990 (a one-piece binder wherein a barb headed post engages and open sided slot).
Those concerned with these problems recognize the need for an improved binder spine.